Exhaust gas control unit



Sept. 29, 1959 J. M. CROUCH ETAL EXHAUST GAS CONTROL UNIT Filed July 8, 1957 INVENTORS JOHN M AY/l/A/VJZ WALL/AIM 5 CO/VLEY fi J ORNEYS Patented Sept. 29, 1959 EXHAUST GAS CONTROL UNIT John M. Crouch and Lyman S. King, San Francisco, and William E. Conley, Richmond, Calif.

Application July 8, 1957, Serial No. 670,551

6 Claims. (Cl. 181-47) This invention generally relates to sound and gas flow control units, silencers, mufflers, and the like, and constitutes an improvement over the apparatus disclosed in a copending application, Ser. No. 489,647, filed February 21, 1955, by John M. Crouch, one of the applicants in the present application.

As is well known in the art, and as set forth in said copending application, mufllers which are used for internal combustion engines, are required to deal with exhaust gases entering the same with a pulsating flow. It is of course necessary that any mufller attachment be arranged so as to prevent the building up of back pressure in the engine which would prevent proper cylinder scavenging, and at the same time must be so arranged as to provide for adequate silencing of the sound created due to the pulsating gas flow. the pulsating gas flow.

It is accordingly an object of the present invention to provide a sound and gas flow control unit in which means are provided for translating the pulsating exhaust flow from an engine into a substantially smooth flow with a minimum of noise and without back pressure build up.

A further object of the invention is to provide a unit of the character described which may be readily attached to any internal combustion engine, in which the gas is caused to follow a number of circuitous paths before being ejected, thereby providing proper silencing of the device and likewise permitting a cooling of the gas and consequent desired reduced volume thereof.

Yet another object of the invention is to provide apparatus of the character described in which an ejector action is utilized for effecting movement of the gas through the unit to the discharge end thereof.

A still further object of the invention is to provide apparatus of the character described including an inlet gas passage and an outlet gas passage which are so arranged as to permit independent thermal expansion of each while being in proper flow communication with each other.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth in the claims.

Referring to said drawing:

Figure 1 is a longitudinal cross sectional view of the sound and gas flow control unit of the present invention.

Figure 2 is a transverse cross sectional view taken substantially in the plane indicated by line 2-2 of Figure 1.

Figure 3 is a transverse cross sectional view taken substantially in the plane indicated by line 3-3 of Figure 1.

As hereinabove explained, the apparatus of the present invention is intended to receive the pulsating exhaust gas flow from an internal combustion engine or the like and cause the gas to flow through the unit while being converted to a substantially non turbulent flow, and likewise causing the gas to follow paths which will result in sound-reflection and absorption. Apparatus for carrying out the foregoing is disclosed in the drawing, and with reference thereto, it will be seen that the instant apparatus includes a central tube 6 adapted to be attached to the exhaust of an internal combustion engine, said tube being adapted to receive the exhaust gases and discharge the same into the remaining portions of the apparatus prior to the final discharge of the gas through an axially aligned tube 7. A cylindrical shell 8 extending longitudinally of and generally encompassing the tubes 6 and 7 has its end portions secured to the respective tubes so that the shell provides a substantially sealed chamber 9 in which the gases are caused to move in a manner presently to be explained. The tube 6 extends through an end 12 of the shell and into the chamber 9 for a distance preferably less than onehalf the length of the shell, and mounted on the tube end in concentric relation is a hollow spherical member 13. The tube 6 enters the sphere generally diametrically through an opening formed in the sphere, and the distal end 14 of the tube is beveled and terminates adjacent the diametrically opposed portion of the sphere. In this manner, gas from the engine entering through the tube 6 will be discharged from the end 14 thereof and into the spherical chamber 16 defined by the member 13. It will be noted in Figures 1 and 3 that the spherical member 13 is provided with a plurality of arcuate openings 17 for a purpose presently to be explained, and the portion of the sphere in aligned relationship to the tube discharge opening is deformed slightly inwardly and thence outwardly to provide an ejector nozzle 18 in alignment with tube 6 for receiving a portion of the gas flowing through the latter.

Referring now to the tube 7 whose distal end 21 provides the gas discharge for the mufiler unit, the end of the tube disposed within the shell 8 is provided with a generally semi-spherical baffle 22 which extends for the greater portion of the diameter of the shell 8 and overlies and is aligned with the ejector 18. Also, additional hoods or baffles 23 of generally semi-spherical configuration are secured to longitudinally spaced portions of the tube 7. The tube 7 throughout the greater portion of the length thereof is provided with a plurality of openings generally indicated at 26 and preferably each of such openings consists of a slot substantially intersecting a longitudinal as well as a transverse axis of the tube. While no exact spacing requirements for the openings are necessary, it is preferable to have each of the hoods or baffles 22 and 23 at its point of connection to the tube 7 generally intersect one of the slots 26. The tube 6 may be provided with similar openings 27, and such openings are likewise formed of the inclined slot type previously described.

With the foregoing structural description, the operation of the unit will now be discussed. Gas from the exhaust of an engine will pass through the tube 6, in the direc tion of the arrows, with a portion of the gas being defiected into the chamber 16 of sphere 13 assisted in this action by the tapered end portion 14, and the remaining portion thereof directed axially through the sphere nozzle 18 into the tube 7. That portion of the gas entering chamber 16, will be permitted to expand and be cooled, and at the same time, the sound waves are repeatedly refiected from the sphere walls so as to be substantially decreased before being permitted to be discharged from the sphere through the openings 17. The portion of the gas passing through the ejector nozzle is directed axially through the tube 7 and due to its relatively high velocity will cause any gas within the shell chamber 9 to be drawn in through the openings 26 and discharged from the end 21 of the tube 7. Thus, while a small portion of the gas is used for the ejector, the bulk of the gas will pass through the spherical chamber, out through the arcuate openings 17 therein and into the chamber 9. Once in the-chamber 9, most of the gas will strike the relatively large hoods or bafiies causing a further reflection and diminishing of sound waves before being pulled through the openings 26 into the tube 7 for discharge. With this arrangement, the sound waves are propagated until substantial attenuation by repeated reflection results, and at the same time the pulsating efiect is changed into a. substantially smooth and continuous discharge flow. Also, the gas is cooled as it passes through the spherical chamber and the shell chamber 9 before being discharged into the atmosphere. Since the tubes 6 and 7 have no direct connection, it will be appreciated that each is capable of independent expansion due to the heat of the gases and consequently none of the stresses encountered by such thermal expansion will be imparted to the other and the unit is capable of operation at extremely high temperatures without danger of structural failure or operational difficulties.

What is claimed is:

l. A sound and gas flow control unit comprising a shell, a first tube extending into said shell, a hollow spherical member entirely within said shell generally encompassing an end of said tube and arranged to receive gas from said tube end, means on said member defining a nozzle extending in general alignment with the end of said tube with the nozzle diameter substantially less than that of said tube, a second tube in alignment with said nozzle, and means defining openings in said member for discharging gas delivered thereto by said first tube into a chamber defined by said shell, and means defining openings in said second tube for receiving gas from said shell chamber and directing the same into said second tube.

2. A sound and gas flow control unit comprising a generally cylindrical shell, a hollow spherical member positioned within said shell and having a nozzle extending axially of said shell, a tube entering said shell from an end thereof and extending diametrically of said member and having an end portion in axial adjacent relationship to the inlet of said nozzle and having a portion within I said sphere, said tube having a greater diameter than said nozzle whereby the major portion of gas flowing through said first tube will enter said member and a lesser portion will flow through said nozzle, a second tube axially entering said shell from the other end thereof and having a distal end portion adjacent the outlet of said nozzle, means defining a plurality of openings in said spherical member whereby gas contained therein may be discharged into the chamber defined by said shell, and

means defining a plurality of openings in said second tube for receiving gas discharged from said spherical member.

3. Apparatus as set forth in claim 2 in which said second tube is provided with a transversely extending semi-spherical hood of a size substantially the same as said spherical member and spaced from the side walls of said shell and overlying said nozzle, said nozzle be ing contained within the axial extent of said hood.

4. Apparatus as set forth in claim 2 in which said second tube is provided with a plurality of generally semi-spherical bafiles positioned along the length thereof with the concave surfaces thereof being disposed towards said nozzle and spaced from the shell. I

5. Apparatus of the character described comprising a generally cylindrical outer shell, a generally spherical member positioned within said shell and spaced from the walls thereof, said member having a restricted opening .in the wall thereof defining a nozzle directed-along the axis of said shell, a first tube having a diameter substantially greater than that of said nozzle disposed along the axis of said shell and entering through an end of the latter and through a wall of said spherical member and terminating in a tapered end portion adjacent said nozzle, said member having a plurality of arcuate openings for discharging gas therefrom into the chamber defined by said shell, a second axially aligned tube entering through the opposite end of said shell and having an end 7 portion disposed in aligned adjacent relationship to said References Cited in the file of this patent UNITED STATES PATENTS 2,035,923 Scarritt Mar. 31, 1936 2,047,442 Starkweather et' al July 14, 1936 2,051,675 Blanchard Aug. 18, 1936 2,055,453 Horton 5 Sept. 22, 1936 2,133,875 Steenstr'up 'Oct. 18,1938 2,138,510 Rauen Nov. 29,1938

" 2,800,973 Cary et al July 30, 1957 FOREIGN PATENTS France Apr. 5, 1932 

